Humans have reached the moon and are planning to return samples from Mars, but when it comes to exploring the land deep beneath our feet, we have only scratched the surface of our planet. This may be about to change with a $1 billion mission to drill 6 km (3.7 miles) beneath the seafloor to reach the Earth’s mantle and bring back the first ever fresh samples.

Geologists involved in the project are already comparing it to the Apollo Moon missions in terms of the value of the samples it could yield. However, in order to reach those samples, the team of international scientists must first find a way to grind their way through ultra-hard rocks with 10 km-long (6.2 miles) drill pipes — a technical challenge that one of the project co-leaders Damon Teagle, from the UK’s University of Southampton calls, “the most challenging endeavor in the history of Earth science.”

Their task will be all the more difficult for being conducted out in the middle of the ocean. It is here that the Earth´s crust is at its thinnest at around 6 km compared to as much as 60 km (37.3 miles) on land. They have already identified three possible locations — all in the Pacific Ocean — where the ocean floor was formed at relatively fast spreading mid-ocean ridges, says Teagle. The hole they will drill will be just 30 cm in width all the way from the ocean floor to inside the mantle — a monumental engineering feat.

To get to the mantle scientists will be relying on a purpose-built Japanese deep-sea drilling vessel called Chikyu, first launched in 2002 and capable of carrying 10 km of drilling pipes.

For Teagle, reaching the Earth’s mantle would provide a “legacy of fundamental scientific knowledge” and “inspire” future generations. If Japanese support can be combined with other funding, Teagle says they could start drilling before the end of the decade, making it possible for humans to finally reach the Earth’s mantle by the early 2020s.

Are you excited about this new project aimed to reach the earth’s mantle? What are your questions about the origins and evolution of the Earth?

Neil Armstrong was a quiet self-described nerdy engineer who became a global hero when as a steely-nerved pilot he made “one giant leap for mankind” with a small step on to the moon. The modest man who had people on Earth entranced and awed from almost a quarter million miles away has died. He was 82. He died following complications resulting from cardiovascular procedures, a statement Saturday from his family said.

Armstrong commanded the Apollo 11 spacecraft that landed on the moon July 20, 1969, capping the most daring of the 20th century’s scientific expeditions. His first words after setting foot on the surface are etched in history books and the memories of those who heard them in a live broadcast: “That’s one small step for (a) man, one giant leap for mankind.”

In those first few moments on the moon, during the climax of heated space race with the then-Soviet Union, Armstrong stopped in what he called “a tender moment” and left a patch commemorate NASA astronauts and Soviet cosmonauts who had died in action. Armstrong and Buzz Aldrin spent nearly three hours walking on the lunar surface, collecting samples, conducting experiments and taking photographs. The moonwalk marked America’s victory in the Cold War space race that began Oct. 4, 1957, with the launch of the Soviet Union’s Sputnik 1, a 184-pound satellite that sent shock waves around the world.

Although he had been a Navy fighter pilot, a test pilot for NASA’s forerunner and an astronaut, Armstrong never allowed himself to be caught up in the celebrity and glamor of the space program: “I am, and ever will be, a white socks, pocket protector, nerdy engineer,” he said in February 2000 in one of his rare public appearances. “And I take a substantial amount of pride in the accomplishments of my profession.”

Armstrong married Carol Knight in 1999, and the couple lived in Indian Hill, a Cincinnati suburb. He had two adult sons from a previous marriage.

Were you among those who watched in awe as Neil Armstrong took his first steps on the moon? Tell us the reasons why you admire this humble, nerdy and accomplished astronaut!